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Thread: "Gluing" together two pieces of lead keel

  1. #1
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    Default "Gluing" together two pieces of lead keel

    For the re-build of my 36' 6mIR, I would like to "glue" end-to-end the two major pieces of the lead keel.

    One piece weighs 3,300 lbs and the other 660 lbs. They have matching faces roughly 6" x 10".

    I would like the joint to be as strong as if the two pieces had been poured as a single piece.

    I don't know whether it is sufficient to pour very hot lead (maybe 1,000° C. - as hot as charcoal will go) in between the two faces or whether I should "cook" the two pieces together.

    I worry that 1.) I shouldn't try to pour 1,000° C. lead and 2.) insufficiently hot lead won't make a good bond with the two massive pieces of "cold" lead.

    My idea for "cooking" is to wrap the ends of the two pieces with a welded sheet steel sleeve, seal the ends of the sleeve with plaster and then build a charcoal furnace around the sleeve. I have no idea how much time to cook so as to get a good bond, without having too much lead melt and having the sleeve and furnace give way.

    Basil

  2. #2
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    I would think that pinning the two pieces together with three or four 5/8ths or so bronze pins might be a more viable solution...
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  3. #3
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    If it's really important to have them be monolithic, why not have it recast - WAY safer, you've got the material, and the foundry has the form, the original bits. Melting large chunks of lead takes lotsa btu's.
    Why are they in two parts anyway?

  4. #4
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    1000 degree lead will put out some terrible lead fumes.

  5. #5
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    You must be kidding. One reason why castings are done in one careful pour is that it's not practical to anneal lead to lead. And of course no glue will hold. If the joint is verticle, just attach each piece to the hull. Usually the j oint is at and angle or lapped in some way to get at least one keel bolt through both pieces. Proper designs don't put the keel strength in lead, so if you must have one piece for strength, look the design over carefully and consider recasting.

    G'luck

  6. #6
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    You should be able to weld them together. It would be necessary to bevel the ends and to make filler rod but that massive a piece could be welded with a large torch. You don't have to melt steel so the torch could be air and propane type.. You probably don't need complete penetration of the weld just the outside 1.5 to 2 inches should be enough to allow it to be handled as one piece.

  7. #7
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    You could take a chainsaw and cut a large “butterfly joint” out of the existing two pieces then just cast the void with a new pour.

  8. #8
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    Take this with 5 or 6 very large grains of salt. I don't have any experience casting large pieces like you're talking about, but I've cast thousands of lead balls for my flintlocks. Speaking from that experience, I haven't found anything that will stick to lead once it's cooled. The butterfly idea sounds good at first, but you've got to remember that lead shrinks as it cools from liquid to solid. The suggestions above to use a mechanical fastening or recast as a single pour seem to be the best approach.
    Al

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    I think that the “shrinking” will make an assembly as tight or tighter than fastenings. This is a common casting technique (using the shrinkage) to obtain a tight assembly. On some metals you would have to be cautious of tearing, but Lead is so soft and malleable this would not be an issue.

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    All metal may and can be welded with the proper fluxes. If not welding then soldering with a 50/50 lead/tin bar solder and an appropriate flux.
    Last edited by ssor; 04-13-2006 at 09:39 PM.

  11. #11
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    Quote Originally Posted by almeyer
    I don't have any experience casting large pieces like you're talking about, but I've cast thousands of lead balls for my flintlocks. Speaking from that experience, I haven't found anything that will stick to lead once it's cooled.
    Al
    People have been successfully soldering lead cames in stained glass work for a few hundred years.

  12. #12
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    I think the ideas of trying to weld the two sections together as you have suggested is a difficult and dangerous proposition.Please don't do that!

    A combination of the butterfly joint and some bronze rod should prove successful,if messy and dangerous.You would probably need at least a 2" gap between the faces to not have the pour metal freeze as it tries to run into the joint..It would probably possible to contain the pour metal with something like Kaowool (available from a potters supplies ) backed by a wooden mould.Edges will have to be molten lead tight!!! Not easy to achieve but if you are only pouring 20 or 30 pound of lead into the joint,if it leaks your could catch it in a big tub of DRY sand and try again.

    A possible problem would be residual moisture in the wooden keel at th top ofthe space .It must be completely dry as molten lead contacting damp wood will cause a steam explosion of great violence.

    If you do any of this work yourself please wear protective clothing and face shields all the time.

    If it was feasible having it recast would be preferable but joining is possible.I'd want to stop and think about each step carefully and in detail before I started.Molten metal can change your life in an instant.

  13. #13
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    Default Recast the smaller section to join the larger with a scarf

    Welding after beveling may well be a practical solution but unless you are comfortable welding AND you have the proper saftey gear AND you are sure that the fumes will not drift through the neighbors house perhaps there is a better way.

    If you were to remove the small piece and cut a steped scarf in the larger piece with a rough face and a few angled bronze pins set into it and then build a form and pour the new section and end up with at worst a good mechanical join.

    Hope it works out and, if you do this thing please document it and share the results.

    **********************
    Notes:

    http://www.esabna.com/EUWeb/OXY_handbook/589oxy17_7.htm

    Lead is a heavy, soft metal, dull gray in appearance except when freshly cut. It has little mechanical strength; large pieces of lead will collapse under their own weight unless properly supported. However, lead has a number of industrial uses – such as the lining of tanks – which require that it be welded. It is always welded with a gas flame, either the oxy-acetylene flame or another oxy-fuel gas flame. The operation is usually termed ”lead burning” by the trade.
    To weld lead is not extremely difficult if you use the proper technique. Whenever possible, lead sheets should be
    connected bylap joints. That is, the sheets should be overlapped 6 to 12 mm, and welds made along each overlapped edge. The metal must be supported during welding. A small welding tip (orifice size less than 1 mm) must be used. The weld cannot be made on a continuous basis; it must be made as a series of overlapping spot welds. Use a flame with a slight excess of acetylene. Hold the torch so that the flame is almost perpendicular to the work surface, with the inner cone almost touching the metal surface. The instant a small puddle has formed, lift the torch away. Then make a new puddle, overlapping the first one. For a lap weld in lead, filler metal usually is not needed. For a butt weld, which may be required occasionally, filler metal can be provided by cutting sheet lead into strips, or by melting lead and pouring it into a channel mold of some kind. Perhaps the most important thing to remember about the welding of lead is that you must scrape all oxides from the surface of the metal before you try to weld it.


    ************

    http://www.occupationalinfo.org/81/819281010.html

    TITLE(s): LEAD BURNER (welding) alternate titles: lead welder

    Welds lead or lead alloy, using gas torch or arc welding equipment, to install and repair lead items according to oral instructions or dimensional data from blueprints: Installs or repairs equipment, such as lead pipes, valves, floors, and tank linings. Cuts lead sheets or pipe, using powered saws, hand shears, or chipping knife. Levels and scrapes edges or surfaces, using hand scraper, and positions parts for burning. Ignites torch and adjusts valves to obtain flame of specified size and color or adjusts arc welding equipment to obtain specified arc. Welds in flat, vertical, horizontal, or overhead positions. Melts lead bar or wire to add lead to joint. Bonds lead to steel or copper to produce homogeneous lead lining or cover, using flux. Places hand molding irons on heavy joints or corners to hold them in position. Heats forms and dresses lead pipes, elbows, and parts, using handtools, torch, or arc welding equipment. Places asbestos strip under joints to prevent heating of supporting surface. May pour molten lead into permanent or sand molds to cast parts. May melt scrap in kettle and cast or extrude melted scrap into bars or wire for reuse. Important variations include type of joint welded (butt, spot, seam).

    ******************

    http://www.macraesbluebook.com/Searc...company=323589

    New England Lead Burning Co., Inc.
    98 Baldwin Ave
    Woburn, MA , 01801-1417
    Phone: 781-933-1940
    FAX: 781-933-4763
    Business Activity: Manufacturer / Exportebr />
    Products Description:
    Radiation shields; lead specialties; tanks; valves, steel fabricators

    **************


  14. #14
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    I'm not much of a metal guy, but welding lead sheating and welding chunks of keel are orders of magnatude apart. Look at any competant keel design. If the keel is more than one piece, usually for convenience of handeling, it has a step joint (or rarely a bevel joint) allowing a keel bolt through both parts, or a simple butt joint such as it appears you have. As you bolt it together, add something squishey as bedding between the pieces and bedding under the wooden keel.

    Don't over-engineer this. It's the wooden keel that holds the lead in place. Not the other way around.

    G'luck

  15. #15
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    I'm curious as to why it's in two parts. Is there some reason for this? One could be that those who cast it orginally couldn't cast it in one part for one reason or another. Another could be that it's easier to handle it in the divided form that it's in. Or it could be that the smaller (aft?) part is meant to be removable if an engine is installed.

    I don't think you'd get any notable strength from welding the two parts together, or from any mechanical bonding. The joint would always be there, something to worry about, and something that would fail if you didn't. Recast it.

    Why do you want to do this? What do you expect to gain?

  16. #16
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    Default Why do this?

    Why do this is really a good question and I think the most important question. But now in the spirit of technical discussion which is sometimes more about the understanding of the details than it is about the merits of the action......
    *****************************

    Welding thick and thin sections are different animals?

    Welding thick and thin sections are usually worlds apart but in the case of lead I think they are not so different. The reason is that large sections are difficult is that it usually takes LARGE amounts of heat to form the puddle because of the relatively high thermal conductivity of metals. However lead is rather low at 35- k (W/m·K) while alum:237, steel:65, stainless:14. The combination of low thermal conductivity and low melting point:620 deg-F make for less problems than many other materials. As a former welder that has NOT welded lead and is speculating, I would be most concerned about the fact that the weld joint was vertical. Set up a couple of ballst pigs and give it a try. An oxy-propane or oxy-actylene small tip welding torch should do it nicely and fuel consumption should be fairly low. The body of the casting would be slow to heat up so if the work were done over a few days it may be possible to do the job and not even cook the old bedding compound out of the top joint.

    ***************
    Wood holds the lead, not the lead holding the wood?

    As a practical matter assuming a the keel timber is in good condition and you don't spend much time pounding on the bottom with the keel it usually would not matter that the ballast was in two sections. However, one of the wonderful things about an external ballast keel is that when it POUNDS on the bottom it (1) protects the wood structure above it and (2) all the heavy inertial loads are contained within the casting and the much more delicate wooden structure above just goes along for the ride. Imagine a boat with internal ballast pounding on the bar in a 4' sea waiting for the tide to rise or the tow boat to arrive. The ballast can/will come right through the bottom in some cases tearing the planks off. A boat with external ballast in the same situation may just shake the teeth out of the captains jaw and break all the wine bottles/glasses while waiting to get off. An external keel casting in two parts when pounded will work hard to tear itself apart. Granted that is an extreame case and even then one is better off than if one had internal ballast. Scarfing the two sections and putting one or two keel bolts thru the scarf seems like it would be near a good as a solid casting.

    *******************

    It is easy for discussions to devolve into 'paralyzed by perfection'. You approach perfection asymptoticly and the most valuable thing a person can know is "What is good enough".

    *******************

    Note: values/units for thermal conductivity ,picked them up from: http://hypertextbook.com/physics/thermal/conduction/

  17. #17
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    I didn't make it through all of the posts but enough to hope you decide to recast. Like Tom Robb said. You've got the material. Pinning...maybe but definately not as strong. Welding, you've got to be kidding! It's lead, lead is soft. Think about when you are out in rough weather...what will you be wishing you did?
    BTW I casted my own ballast, 10,000 lbs. If I can do it anybody can. If not that route..it's worth having it done.

  18. #18
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    Since there has been no reply from the questioner, and many more or less reasonable responses, I'm beginning to wonder if this is a troll?
    As an old TelCo guy who has had to solder lead sheathed cables back in the day before plastic sheathed cables, I gotta say it's damn hard to get the "touch" where you melt just enough, even granting the thin lead on a cable is perhaps a different animal than a chunk of keel ballast.
    Sounds like a fool's errand to me.

  19. #19
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    Thanks to Paladin, Tom Robb, George Roberts, Ian McColgin, ssor, Canoeyawl, almeyer, Peter Sibley, George Ray, htom, mariner2k and Tom Robb for your comments.

    I don’t know what a “troll” is, but please be assured that I’m an authentic, if inexperienced, re-builder of a 75 year-old 36’ racing sloop. I was a bit overwhelmed by all the comments and needed time to sort them out.

    As for details which I didn’t think to specify in my question:

    - the two pieces are free-standing. They are not attached to the keel.
    - there is no obvious way to get a bolt through both pieces

    I learned that the “gluing” I mentioned is called “lead burning” in the trade. (George Ray)

    As to why the keel is in two pieces, I’ll probably never know. You will find below an imaginary conversation, between the architect and the person who commissioned the boat, during the summer of 1935 which tries to explain the various anomalies which I have observed.

    I think that George Ray’s comments explain why I would like to have the ballast keel be in one piece. Reasoning by extremes, and since there are 10 keel bolts in all, I prefer to have one piece held by 10 bolts rather than 10 pieces each held by one bolt.

    The various solutions proposed were:

    - use bronze pins to join the two pieces together (paladin, Peter Sibley, George Ray)

    - recast all 4000 lbs (Tom Robb, htom, mariner 2j)

    - weld the two pieces together (ssor, George Ray)

    - pour a butterfly joint (Canoeyawl, Peter Sibley)

    - put a stepped scarf, pin the pieces together and pour the joint (George Ray)

    Other useful comments dealt with:

    - experiment with ballast pigs (George Ray)

    - lead’s low thermal conductivity will permit localized heating of the two faces, without the heat being quickly dissipated throughout all the metal (George Ray)

    - the danger of fumes at 1,000° C. (George Roberts)

    - nothing sticks to cold lead (almeyer)

    - weld only if comfortable with the technique, properly equipped and far away from neighbours (George Ray)

    - put a big tub of sand under the pieces if pouring (Peter Sibley)

    - everything that the molten mead might touch must be very dry (Peter Sibley)

    - scrape all the oxides off the metal before “burning” (George Ray)

    Thanks to all these ideas, I plan to:

    - experiment with ballast pigs

    - use a four 16 mm. bronze pins,

    - buy the necessary safety geabr />
    - scrape all the oxides off,

    - keep everything dry,

    - put a tub of sand under my apparatus,

    - favour a lead burning approach, along the lines of my original idea, with a steel mold and a charcoal furnace.

    I will keep you informed of the results – and thanks again.

    Basil Carmody

    “Drewitz: Mr Collignon, you've asked me to design a boat for you with which you can win the 1936 Olympics. As you know, I'm a specialist of H-Jollens, so I'm not in a position to propose a Six metre design based on years of experience, representing the latest step in my trying to come up with the ideal design.

    Collignon: Yes, I fully understand this. I could have asked any one of a number of Six metre architects to give me their latest design, but they would have given similar designs to other clients. I wouldn't have benefited from a quantum leap forward in the boat I'd have built. I turned to you because you're an original thinker, capable of thinking outside of the box, in the hope that you could come up with a radical design which would give me a chance to win a gold medal.

    Drewitz: O.k. We understand each other. Now hold on to your hat. I've come up with a plan for a boat with two very different waterline lengths. One length, when the boat is empty, is the one used for it to measure as a Six. It's ultra short (5,60 m.), thus allowing me to add lots of sail area (over 50 square meters) and to give her an extreme wine-glass cross-section which is normally heavily penalised because of the “chain girth” parameter of the International Rule. The other waterline (7,10 m.), when the crew is aboard, is much, much longer, thus creating a real increase in maximum hull speed.

    Collignon: That sounds great. Tell me more.
    Drewitz: I told you to hold on to your hat. So here goes. I've designed the boat so that the helmsman sits in - I admit it's tight - a 30" hatch aft of rudder shaft. Also, the other crew members are positioned in the aft end of the cockpit.

    Collignon: How can a helmsman be aft of the rudder?

    Drewitz: Although the rudder shaft is forward of the helmsman, I’ve included a system, based on the same parts used for steering wheel systems, which links the tiller to the rudder shaft. The tiller emerges from the deck a few centimetres forward of the transom.

    Collignon: My God, man, you’re out of your mind. There's no way that I'm going to show up at the German Olympics Trials with a boat designed by a first time Six metre architect with me cramped in a tiny hatch and the tiller positioned just forward of the transom. I'll be the laughing stock of the entire German yachting community.

    Drewitz: No, I'm not out of my mind. In fact, I’m placing you in the best position to look around your genoa to see what's happening to leeward.

    Collignon: I'm flabbergasted by your stupidity. I've wasted my money on you. I don't want to hear anything more about this boat.

    Drewitz: I'm extremely distressed by your reaction Mr Collignon, but the boat is virtually finished. Mr Buchholz is at the point of bolting the keel to the hull. I assure you that the boat will be very rapid, but it has to be sailed with the helmsman in the rear hatch.

    Collignon: I don't want a boat in which I would be stuffed like a sardine in a 30" shallow rear hatch. I don't care what it takes. I want that boat converted to a normal Six.

    Drewitz: Yes, sir. The client is always right. I'll tell Mr Buchholz to take three chunks out of the forward part of the lead keel and to add 264 lbs. of lead ingots just forward of the sternpost, to compensate for the change in position of the crew members.
    I’ll also tell him to place the tiller in the traditional position. Because of the remote steering system, the rudder shaft emerges only a few inches into the hull. I’ll have to use the same system for the new tiller, even though, in a traditional Six, it would normally be linked directly to the rudder shaft.
    By the way, I doubt that the boat will measure as a Six in this new configuration.
    Do you want me to also have the rear hatch decked over?

    Collignon: All I want is to spend a minimum amount of money to turn your wretched idea into something that resembles a normal Six. Tell Buchholz to change the weight distribution and to move the tiller, but leave the rear hatch as it is. ... hmmm ... Mr Thomsen of Kiel is having a new Six, Gustel V, built by Wilke. Maybe he’ll sell me his old boat, Gustel IV, so that I can at least participate in the Olympic Trials
    Hmmm … and I wonder who would be stupid enough to buy Drewitz’s monstrosity. One can usually talk the good Dr Tubiak into anything. It will be fun to see if I can unload it on him.”

  20. #20
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    I have to say that Basil is not a Troll. He is trying to restore his six-metre and does a lot of research in how to do it right. It's a very uncommon boat since it was constructed by the famous dinghy designer Drewitz (who - by the way - made a speed record of 28 knots in 1938 in his Z-Jolle).

  21. #21
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    Basil wouldn't be A Troll, the post itself was beginning to look like one to me. Trolls here have been posts designed to promote controversy rather than honest exchanges of information. It's trolling as in towing bait behind one's boat in the hope that some fish will bite.
    Since he hasn't got ten chunks of lead with one bolt each, reasoning by extremes would not seem to apply.
    Doing it "right" would probably involve recasting the ballast, but one is always free to chose.

  22. #22
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    I have had a bit of experience with lead and I think Yes, you can “Weld” it.
    But… think about welding two ice cubes together, you are going to need a form!
    Now if you pack sand around it that will work, but you will now have solid lead with sand imbedded in it and it’s tough to plane it or finish it. I know this one from experience!!!
    I would make a simple form from steel and gasket and clamp it around the weld area to retain the molten metal; lead does not “freeze” like metals that are normally welded and some of your joint will surely be “out of position”.
    This is common practice for welding any metals with a large gap that is out of position. Welding steel for example you would use a copper “back-up” to avoid joining.

  23. #23
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    George ray what you are describing was described by Bud in his book. He told a story of a customer wanting internal ballast. He told him to take an iron and hit the top of a table with it. Once with his hand over it and once with his hand under it. Made sense to me as well

  24. #24
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    I could do this weld on your keel sections.

    The problem is thickness....and the form work required to contain the large amount of puddling due to the large bevels caused by that thickness....and to keep the unit from sagging....would be as much work as melting down and recasting it as one unit.

    But you can try it. I'd advise using the existing keel sections as patterns to either build a proper mold or at least doorskin patterns you can build a mold with if you wind up reaching my conclusion after attempting to burn in lead that large.
    Last edited by Bob Smalser; 04-15-2006 at 08:11 PM.

  25. #25
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    I think that one of the problems here has been an understanding of "Welding". Welding is the joining of like metals by fusion. Aluminum can be joined to aluminum by welding. steel to steel, lead melts at such a low temperture that the term welding seems inappropriate but by melting the faces of the large pieces and adding a filler and removing the heat a weld will happen. This process is continued first across the top then the piece would be rolled and the weld would continue until the entire circumference had been welded. As Bob S states recasting may be easier if those facilities are available.

  26. #26
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    Thank you again for your comments - and what a pleasant surprise to see my German friend, Ingo List, among the respondents. (Ingo is the master of European classic yacht registers. I'm in the process of preparing the complete register of all +/- 1500 6 metre yachts built since 1907, which will be added to Ingo's registers - see www.fky.org. We're hoping that some day WoodenBoat will decide to link its register with Ingo's registers, a step which would represent a major advance toward a seamless worldwide network of classic boat registers.)

    I am planning to prepare a complete technical memorandum on burning my two pieces of lead together. It will start with estimates of the heat required and its temperature diffusion profile within the two pieces of lead. It will identify key questions to resolve with pilot experiments. It will include a complete description of the work to be done. I won't start anything until the memo is completed.

    The work procedure will surely change during the process, but any change will have to fit into the overall process.

    I will provide updates from time to time until the end.

    Thanks again,

    Basil

  27. #27
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    Basil,

    Thanks for the link to www.fky.org. What a great site. Google can provide a (rough) translation for those interested.

    We would be very interested in seing photos of your project.

  28. #28
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    Default What is good enough?

    After reading all the comments:

    (1) IF I THOUGHT I NEEDED TO UNITIZE THE KEEL:

    SCARF-BOLT:
    IF, I thought I needed to 'unitize the external ballast keel' with the large section still bolted in place, I would be most comfortable following up on Ian's comment and recasting the smaller section with a long enough step scarf to include one keel bolt and maybe a bronze drift pin or two. Cutting the scarf in the larger section would not be too bad. A carpenters "RIP Saw", kerosene for lube and a jig to maintain saw cut alignment would get the job done fairly quickly. The rip saw blade tooth shape minimizes the clogging that plagues folks trying to cut lead. Crosscut blade teeth become hopelessly mired down in no time, and chain saws work but you won't get an accurate smooth faced cut.


    WELD-IN-PLACE:
    If welding in place I would bevel the sections as they are bolted on by making two saw cuts (using tools from #1 above) from the bottom up. The cuts would be an "X" that is centerd on the seam and would result in a 45 deg bevel on each side. A copper sheet/plate and maybe some plywood shields would be fit up against the wood keel above to protect it from the rising heat of the torch. (lots of cast-off/byproduct heat there). The vertical welds would be done using 1/8" to 3/16" filler rods cast from the material cut out to make the bevel. (a project in itself) The welding with such a small puddle/filler rod size would take a month of sundays and the boat above would try to dry out with out protection/shielding. If it were possible I would loosen the keel boats and lift the wooden structure off the lead keel, insert sacrificial plywood between the keel and lead and temporarily secure with all-thread in place of the keel bolts. That would maintain alignment and isolate the wood from the heat of welding. The plywood shield would end up badly scorched. A piece of copper plate would be set into the plywood directly above the welding.


    WELD-IN-SHOP:
    If welding the sections off the boat, it is BIG challenge to keep the exisiting holes on the two pieces aligned so they will fit when put back on the boat. (pattern jig made from the boat to maintain hole spacing and axial alignment. -> nontrivial task). Oh and what about moving the pieces around? Move keel to boat or boat to keel? ... If the keel is separated from the boat and somehow aligned and tacked togeather you might be able to set it up to rotate and then all the welds after tacking can be done 'downhand/flat/horizontal' and rod size can increase and progress is made much more quickly.....But now you have to worry about the weld drawing the sections out of alignment unless you CAREFULLY weld alternate side and that means rotating the section for every pass and maintaining alignment while rotating the two ton chunk of lead. mmmmmm. think it might be easier to weld in place even with the vertical weld seams and the heat shields and the small filler rod/puddle that means it will take ?????SWAG=>1000 passes to fill out the 6" x 10" section beveled to 45 degrees. ... 10 minutes/pass => 10,000 minutes => 160 welding hours not counting all the waiting to cool down time.. Recasting is looking better all the time.


    RECAST:
    Support the vessel over the top of a sectional ballast keel form (3 piece- bottom & 2 sides) with a layer of insulating/sacrificial plywood between the bottom of the keel and the top of the form. Holes for the keel bolts bored through the plywood and steel rods the same size as keel bolts inserted. Soot from rich yellow torch flame coating the rods and the bottom of the plywood (non-stick/release agent). Form sides set in place, secured and lead poured. Rods pulled (slide hammer) out the top, plywood removed, bedding coumpound applyed to top of lead and bottom of keel and hull allowed to settle down on the lead with the keel bolts in place. Remove the bottom of the form and dig out the filler pieces (refractory clay?) that form the keel bottom recesses for the keel bolt bottom washer/nut. Don't forget wicking and goop under the washer/nut before tightening down and painting and going sailing.

    ******************

    (2) IF I WERE NOT SURE WHAT TO DO:

    KEELBOLTS:
    Remove and inspect and refit with a generous use of beeswax/tallow goop to protect and ensure that they can be removed easily later.

    INTERIOR LAYOUT:
    Ensure that the interior design allows easy access to the bolts being pulled upward (slide hammer).

    HULL STRUCTURE
    Ensure that the hull structure/frames/floors/keel is comfortable being cradled and supporting the weight of the ballast for a short time while preparing to drop keel and recast.

    THINK ABOUT IT:
    Fix everything else and go sailing for a while and the answer will come to you in a dream as your sleeping in a quiet anchorage somewhere.

  29. #29
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    George Ray, Very good carefully considered response.

  30. #30
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    Apr 1999
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    Now, there's a long story...
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    Based on my knowledge of metre boats... it's entirely likely that the smaller piece was added in order to address issues found after the original launch. Then, it would make sense to simply add a piece rather than re-cast the keel.

    I say this as a guy with an Eight, whose keelbolts no longer even go through floors. Because the boat was overbuilt to start, there has been no weakness due to this apparent faux pas. Just a few surveyors shaking their heads.

    My Eight also has a hatch aft of the rudder post... but it's actually a little smaller than what you've mentioned. I'd never try to steer from back there, as the boat is sensitive to weight aft. So much so that a PO added a LOT of fairling material in order to increase displacement. It didn't really work, but the surveyor and I had to do some destructive testing to determine that the boat was not delaminating.

    Also, Length, in the rule, is not measured at the waterline, but at a point above the true waterline. And the chain girth can be traded off for length, sail area, or freeboard. You pays your money and you takes your chances...

    remember: 6m=(L+2d-F+(sqrt(S)))/2.37
    Heute ist so ein schöne Tag...

  31. #31
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    Jun 2003
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    We may be over engineering this job; I think a simple J-groove set-up using an oxy-acetylene #6 or #7 tip with back up strips will do it. The j-groove will only need to be wide enough to fit the torch, only about ½ inch or so.
    The ballast will need to be fixtured to match the existing bolt holes and leave a gap for the J-groove, but it’s heavy and won’t move around much so this should be simple. Some plate and clamps will do this and provide the back up strips. Once the weld is started, it should be fine. I would use steel or aluminum back-up so that the lead will not “solder” itself to the fixture.
    I don’t think it should take over a day to do the job.



  32. #32
    Join Date
    Dec 2002
    Location
    France
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    15

    Default

    Again, thanks to George Ray, ssor, Canoeyawl and Dave Lesser for your comments.

    Since I don’t have oxyacetylene welding equipment, I’m still inclined to try my charcoal furnace.

    The forty 3 kg. lead ingots I pulled out of the tar and lead “fruitcake”, just forward of the sternpost, provide me with an abundance of small pieces of lead to experiment with beforehand.

    Dave Lesser mentioned having visited the fky.org site and also suggested I post pictures of my Six, Joanna.

    I don’t know if Dave noticed that the FKY has scanned 170,000 pages of the two principal German yachting magazines, going back to the 19th c., and made them available on the Web with complete word search capabilities. In France, I’m trying to help along a project to scan the major French yachting magazine, also going back to the 19th c.

    The key person behind all these riches is Ingo List, a Ph.D. theoretical physicist, founder of his own software firm at age 18 (Antares Project GmbH), owner of a classic sailboat and one of the most friendly, available and helpful people I’ve met on the Web. Behind Ingo is Wilfried Horns, the president of the FKY, who has the rare ability to recruit and motivate many people like Ingo.

    FKY is spearheading a project called e-AHOY to link all the classic yacht databases of Europe into a seamless network.

    If I’m so enthusiastic about FKY (and I’m part of a [still] small group of people in France who are trying to create a French equivalent of the FKY), it’s because they steered me to the specific page of Die Yacht in 1935which contained a launching picture of my Joanna. A query with the name of the architect (Drewitz) and the German way of abbreviating Six Metre International Rule (6mr) as search terms pops up the first picture below.

    The translation of the German text is:

    An unusually newly built 6mIR

    From the shipyard of W. Buchholz comes a truly unusual 6mIR yacht designed by R. (Reinhold) Drewitz for Dr Collignon of the Wannsee Sailing Yacht Club. The strongly divergent form of craft, not only with respect to the International Rule boats, but also with respect to other customary sound sailing yachts, is indicated by the pictures above. The length overall of the boat is some 70 cm. shorter and its waterline length some 1,50 m. shorter than normal Sixes. Therefore it has an unusually long counter and it is 35 to 40 cm. wider than normal sailboats. The stem progresses in a straight line from the forepeak to the keel. The dimensions of the hull permit a significantly greater sail area, in excess of 50 m². This advantage is possible because the boat, in addition to its measured plane of flotation, has a second plane of flotation when it sails. This change in trim is accomplished by the crew being situated fully aft.

    Key features detectable from the pictures

    • Long boom and no permanent backstay
    • Boom crutch which resembles its current boom crutch
    • Parallelogram shaped rudder as currently on the boat
    • Mast stepped fairly far forward
    • Shroud and two sidestays

    I wanted to post additional pictures, but – despite a 39kB maximum announced – I only managed to attach this 10kB picture without exceeding the limit.

    Best wishes,

    Basil

  33. #33
    Join Date
    Dec 2002
    Location
    France
    Posts
    15

    Default Failed attempt to attach a photo

    I uploaded the picture, but I don't see it posted.

    I also don't know how to clear the picture from my quota.

    Basil

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